/Engine/Source/Runtime/Engine/Classes/Kismet/KismetRenderingLibrary.h
Incredibly inefficient and slow operation! Read an area of values as-is from a render target using a rectangle defined by UV [0,1]x[0,1] coordinates.
static [TArray](API\Runtime\Core\Containers\TArray)< [FLinearColor](API\Runtime\Core\Math\FLinearColor) > ReadRenderTargetRawUVArea ( [UObject](API\Runtime\CoreUObject\UObject\UObject) * WorldContextObject, [UTextureRenderTarget2D](API\Runtime\Engine\Engine\UTextureRenderTarget2D) * TextureRenderTarget, FBox2D Area, bool bNormalize )